Как сохранить захваченное изображение в каталоге документов

Я захватил изображение, используя приведенный ниже код

AVCaptureSession *session = [[AVCaptureSession alloc] init];
session.sessionPreset = AVCaptureSessionPresetMedium;

CALayer *viewLayer = self.vImagePreview.layer;
NSLog(@"viewLayer = %@", viewLayer);

AVCaptureVideoPreviewLayer *captureVideoPreviewLayer = [[AVCaptureVideoPreviewLayer alloc] initWithSession:session];

captureVideoPreviewLayer.frame = self.vImagePreview.bounds;
[self.vImagePreview.layer addSublayer:captureVideoPreviewLayer];

AVCaptureDevice *device = [AVCaptureDevice defaultDeviceWithMediaType:AVMediaTypeVideo];

NSError *error = nil;
AVCaptureDeviceInput *input = [AVCaptureDeviceInput deviceInputWithDevice:device error:&error];
if (!input) {
    // Handle the error appropriately.
    NSLog(@"ERROR: trying to open camera: %@", error);
}
[session addInput:input];

[session startRunning];

_stillImageOutput = [[AVCaptureStillImageOutput alloc] init];
NSDictionary *outputSettings = [[NSDictionary alloc] initWithObjectsAndKeys: AVVideoCodecJPEG, AVVideoCodecKey, nil];
[_stillImageOutput setOutputSettings:outputSettings];

[session addOutput:_stillImageOutput];

когда я нажимаю кнопку

   AVCaptureConnection *videoConnection = nil;
       for (AVCaptureConnection *connection in _stillImageOutput.connections)
{
    for (AVCaptureInputPort *port in [connection inputPorts])
    {
        if ([[port mediaType] isEqual:AVMediaTypeVideo] )
        {
            videoConnection = connection;
            break;
        }
    }
    if (videoConnection) { break; }
}

NSLog(@"about to request a capture from: %@", _stillImageOutput);
[_stillImageOutput captureStillImageAsynchronouslyFromConnection:videoConnection completionHandler: ^(CMSampleBufferRef imageSampleBuffer, NSError *error)
 {
     CFDictionaryRef exifAttachments = CMGetAttachment( imageSampleBuffer, kCGImagePropertyExifDictionary, NULL);
     if (exifAttachments)
     {
         // Do something with the attachments.
         NSLog(@"attachements: %@", exifAttachments);
     }
     else
         NSLog(@"no attachments");

     NSData *imageData = [AVCaptureStillImageOutput jpegStillImageNSDataRepresentation:imageSampleBuffer];
     UIImage *image = [[UIImage alloc] initWithData:imageData];



     self.vImage.image = image;
     _vImage.hidden=YES;
     UIStoryboard *storybord=[UIStoryboard storyboardWithName:@"Main" bundle:nil];

     shareViewController   *shareview=[storybord instantiateViewControllerWithIdentifier:@"share"];
     [self presentViewController:shareview animated:YES completion:nil];

     shareview.shareimageview.image=image;

     NSMutableArray *temparray = [NSMutableArray arrayWithObjects:image,nil];
    NSMutableArray  *newparsetile=[@[@"you"]mutableCopy];
     shareview.newtile=newparsetile;
     shareview.selectedimgarray=temparray;


     [[NSNotificationCenter defaultCenter] postNotificationName:@"Shareimage" object:image];


 }];

как сохранить выходное изображение в каталоге документов устройства, может ли кто-нибудь помочь мне, ответ с кодом приветствуется, так как я новичок в цели ios c, люди, которые хотят настроить камеру, например instagram, могут использовать мой код это 100% работает